Connector modules to optically connect to electronic devices

ABSTRACT

A modular connector infrastructure includes device connector modules having optical connectors to optically connect to respective subsets of electronic devices in a system. The device connector modules are removably connected to the electronic devices.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a national stage application under 35 U.S.C. §371 ofPCT/US2012/020438, filed Jan. 6, 2012.

BACKGROUND

A system can include multiple electronic devices. To allow communicationwith the electronic devices, a backplane infrastructure can be providedin the system, where the backplane infrastructure has connectors toconnect with respective mating connectors of the electronic devices. Theconnectors of the backplane infrastructure can include opticalconnectors to optically connect to respective electronic devices.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments are described with respect to the following figures:

FIG. 1 is a schematic perspective view of a rack including electronicdevices, according to some implementations;

FIGS. 2A-2B, 4A-4C, and 5A-5B illustrate various example modularconnector infrastructures for optically connecting electronic devices,according to various implementations;

FIGS. 3A-3B illustrate an example connector module according to someimplementations;

FIGS. 6 and 7 are rear views of example racks that include plenums forreceiving connector modules according to some implementations;

FIG. 8 is a rear view of an example rack having device connector modulesinterconnected by an interconnecting connector module, according to someimplementations; and

FIG. 9 is a flow diagram of a process of assembling a modular connectorinfrastructure, according to some implementations.

DETAILED DESCRIPTION

Electronic devices, such as processing devices, storage devices,communications devices, management devices, and so forth, can be mountedin a rack, which includes a frame and other support elements for holdingthe electronic devices. The rack provides receptacles into which theelectronic devices can be inserted. The rack can also include abackplane infrastructure for connection to the electronic devices thathave been inserted into the rack. Generally, the backplaneinfrastructure can include a support structure to which connectors areattached. When electronic devices are mounted in the rack, connectors onthe electronic devices can mate with connectors of the backplaneinfrastructure. The connectors of the backplane infrastructure areconnected to communications media (e.g. optical fibers, electricalwires, etc.) to allow for communication among the electronic devices.

A backplane infrastructure can include optical connectors for opticalconnection with respective optical connectors of the electronic devices.It is noted that the electronic devices and the connector infrastructurecan also include electrical connectors for electrically connecting theelectronic devices to the backplane infrastructure. In the ensuingdiscussion, reference is made to just optical connectors—note, however,that it is to be understood that various components discussed below canalso additionally include electrical connectors.

In some examples, a backplane infrastructure can include an integratedand fixed arrangement of optical connectors for connection to respectiveelectronic devices. An integrated and fixed arrangement of opticalconnectors refers to an arrangement in which the optical connectors areaffixed to a support structure of the backplane infrastructure such thatthe optical connectors are not separable from one another. This canpresent an issue when the backplane infrastructure is to be accessed forservice (e.g. to repair a defective component) or upgrade (e.g. toreplace a component). For example, to access the backplaneinfrastructure for service or upgrade, the electronic devices of thesystem may have to be dismounted, which disrupts system operation.

Also the arrangement of the optical connectors on the backplaneinfrastructure can be for a specific system design, which means that adifferent backplane infrastructure having its respective differentarrangement of optical connectors would have to be provided for adifferent system design. As a result, backplane infrastructures havingintegrated and fixed arrangements of optical connectors are associatedwith reduced flexibility.

To provide improved flexibility, a modular connector infrastructureaccording to some implementations is provided. The modular connectorinfrastructure includes multiple device connector modules that areindependently and removably connected to respective subsets ofelectronic devices. The device connector modules are independently andremovably connected to respective subsets of electronic devices if oneof the device connector modules can remain connected to a first subsetof electronic devices while another of the device connector modules isremoved (or separated) from a second subset of electronic devices.

The modular connector infrastructure can also include interconnectingconnector modules for optically interconnecting device connectormodules; an interconnecting connector module can connect the deviceconnector modules to each other. The interconnecting connector module isremovably connected to the device connector modules.

Each connector module (device connector module or interconnectingconnector module) includes optical connectors and optical communicationsmedia (e.g. optical fibers, optical waveguides, etc.) connected to suchoptical connectors. An optical connector can include optical elements(e.g. lenses, ferrules, etc.) to allow for communication of opticalsignals. The optical communications media allow for opticalcommunications among the electronic devices in a rack. In some examples,the device connector modules and interconnecting modules can alsoinclude electrical connectors and electrical communications media.

The modularity of the modular connector infrastructure allows for a userto remove just the connector module(s) that is (are) to be serviced orupgraded, such that the remaining connector modules of the modularconnector infrastructure can remain attached to respective electronicdevices in the system. Additionally, the modularity of the modularconnector infrastructure allows the arrangement of optical connectors tobe easily changed for different system designs. For example, differentsystems can employ different connection topologies (e.g. star connectiontopology, mesh connection topology, etc.)—the arrangement and/or typesof connector modules of the modular connector infrastructure can beflexibly and easily changed to accommodate the different system designs.As further examples, the modular connector infrastructure can be changedto achieve other system goals, such as to meet physical spacespecifications, power specifications, cooling specifications, signalbandwidth specifications, and so forth.

In addition to modularity, redundancy can also be provided with themodular connector infrastructure in accordance with someimplementations. Redundancy can be provided by associating at least apair of device connector modules with each subset of electronic devices.Thus, when one of the pair of device connector modules is detached froma given subset of electronic devices, the electronic devices in thegiven subset can continue to operate using the other device connectormodule in the pair. In this manner, during servicing or upgrade of aparticular device connector module, the given subset of electronicdevices does not have to be turned off, which allows for continuedsystem operation. Note that redundant interconnecting connector modulescan also be used—if one interconnecting connector module is removed forservicing or upgrading, the other, redundant interconnecting connectormodule can remain connected to the device connector modules to allownormal system operation to continue.

FIG. 1 illustrates an example system 100 that has a rack 102 thatincludes various electronic devices 104. The rack 102 includes anexternal chassis (or frame) containing receptacles 105 into whichrespective electronic devices 104 can be inserted. Although not shown inFIG. 1, the rear portion of the rack 102 includes a modular connectorinfrastructure having connector modules for connecting to electronicdevices 104 that have been mounted in the rack 102.

FIG. 2A illustrates an example of the modular connector infrastructureaccording to some implementations. Electronic devices 104 can bearranged generally in an array (having rows and columns of electronicdevices 104). Two types of connector modules are provided in the modularconnector infrastructure of FIG. 2A. The first type includes deviceconnector modules 202 that are connected to respective subsets of theelectronic devices 104. In examples according to FIG. 2A, the deviceconnector modules 202 are vertical device connector modules 202, whereeach vertical device connector module 202 is connected to acorresponding column of electronic devices 104.

Although the interconnecting connector module 204 is shown to have ahorizontal orientation in examples according to FIG. 2A, note that inalternative examples, the interconnecting connector module 204 can haveother orientations.

A second type of connector module includes an interconnecting connectormodule 204 for interconnecting the device connector modules 202. In thisway, an electronic device 104 in a particular subset can opticallycommunicate with another component (another electronic device 104 inanother subset or a component that is within the rack) through theelectronic device's device connector module 202 and the interconnectingconnector module 204.

Note that the electronic devices 104 shown in FIG. 2A do not have to bethe same type of electronic devices. There can be various differenttypes of electronic devices 104 mounted in the rack 102 of FIG. 1. Forexample, some electronic devices can be processing devices (e.g.computers, processor nodes, etc.), while other electronic devices can bestorage devices (e.g. hard disk drives, integrated circuit storagedevices, etc.) and/or communications devices (e.g. switches, routers,etc.) and/or management devices (e.g. devices to manage other devices,such as to activate or deactivate devices, collect status or measurementinformation of devices, manage power or cooling of devices, etc.).

As a specific example, the first row of network devices 104 shown inFIG. 2A can include communications devices, while the second and thirdrows of electronic devices 104 shown in FIG. 2A can include processingdevices. Each vertical device connector module 202 can connect theprocessing devices to the respective communications device, but theprocessing devices in each column are not connected to each other. Suchan arrangement is referred to as the star topology, since each givencommunications device in a column is connected to its respectiveprocessing devices, but the processing devices are not connecteddirectly to each other. In other arrangements, other connectiontopologies can be provided. For example, a mesh topology can beprovided, where the electronic devices in a column can be connected toeach other (e.g. processing devices can be connected to each other, orcommunications devices can be connected to each other).

Each of the electronic devices can include an optical interface coupledto the optical connector of the electronic device. The optical interfacecan convert between optical signals and electrical signals, where theelectrical signals are used by various components (e.g. processor,input/output device, memory device, etc.) in the electronic device.

FIG. 2B illustrates a modular connector infrastructure according todifferent implementations. In FIG. 2B, device connector modules 202 areconnected to respective columns of electronic devices 104 (similar toFIG. 2A). However, in FIG. 2B, a pair 210 of interconnecting connectormodules 212 and 214 are provided (instead of just the singleinterconnecting connector module 204 in the FIG. 2A). The multipleinterconnecting connector modules 212 and 214 are used to interconnectthe device connector modules 202. In some examples, the multipleinterconnecting connector modules 212 and 214 are redundantinterconnecting connector modules (where one of the redundantinterconnecting connector modules can allow for continued communicationseven if the other interconnecting connector module is removed or hasfailed).

In other examples, the multiple interconnecting connector modules 212and 214 are not redundant interconnecting connector modules, but ratherare connected in parallel to the device connector modules 202 to providefor increased communications bandwidth—for example, the interconnectingconnector modules 212 and 214 are connected to the device connectormodules 202 in a way that allows the interconnecting connector modules212 and 214 to carry different sets of optical signals. In otherexamples, it is possible for the interconnecting connector module 212 tobe connected at the top ends of the device connector modules 202, whilethe other interconnecting connector module 214 is connected at thebottom ends of the device connector modules 202.

The connector modules of the modular connector infrastructure depictedin FIG. 2A or 2B are accessible without having to remove the electronicdevices 104 from the rack. In this way, a user can easily removeselected connector modules from the modular connector infrastructure toperform service or upgrades, or for changing the configuration of themodular connector infrastructure to provide a different system design.

FIGS. 3A and 3B illustrate an example of a device connector module 202.FIG. 3A illustrates a front view of the device connector module 202,while FIG. 3B shows a rear view of the device connector module 202.Although reference is made to a “front view” or “rear view” with respectto FIGS. 3A and 3B, it is noted that from a different perspective, theview of FIG. 3A can be considered the rear view while the view of FIG.3B is considered the front view.

The device connector module 202 has first type optical connectors 302-1,302-2 and second type optical connectors 304-1, 304-2. In some examples,the first type optical connectors 302-1, 302-2 can be used to connect tofirst type electronic devices (e.g. communications devices). The secondtype optical connectors 304-1, 304-2 can be used to connect to secondtype electronic devices, such as processing devices or other types ofdevices.

The optical connectors 302-1, 302-2 and 304-1, 304-2 are mounted on ahousing 306 of the device connector module 202. The housing 306 can begenerally U-shaped, although in different examples, the housing 306 canhave other shapes. The generally U-shaped housing 306 defines an innerchamber 308. Although not shown in FIG. 3B, optical communications media(e.g. optical fibers or optical waveguides) can be provided in the innerspace 308 of the housing 306. The optical communications media areoptically connected to corresponding optical connectors 302-1, 302-2 and304-1, 304-2.

In some examples, the device connector module 202 is mounted into a rack(e.g. 102 in FIG. 1) by sliding the device connector module 202 into, arespective receiving structure in the rack. As explained further below,this receiving structure can include a plenum that defines an elongatedgroove into which a device connector module can be inserted. Uponinsertion of the device connector module 202 into the receivingstructure in the rack, the optical connectors 302-1, 302-2 and 304-1,304-2 (on the side of the support structure 306 depicted in FIG. 3A) aremated to respective optical connectors of corresponding electronicdevices 104.

The optical connection between optical connectors of the deviceconnector module 202 and optical connectors of electronic devices caninclude a blind-mate optical connection. A “blind-mate opticalconnection” refers to an optical connection in which one opticalconnector can be connected to another optical connector, with alignmentbetween the connectors being automatically performed using alignmentfeatures, such that a user does not have to visually align connectors tomake the connection.

Although FIGS. 3A-3B illustrate a specific configuration of a deviceconnector module 202, note that an interconnecting connector module 204,212, or 214 can have a similar configuration that includes a supportstructure, optical connectors mounted on the support structure, andoptical communications media to optically interconnect the opticalconnectors. The optical connectors of the interconnecting connectormodule can also be blind-mated to the optical connectors of the deviceconnector modules 202.

In other examples, instead of one integral device connector module 202,two separate device connector modules can be provided, with the twoseparate device connector modules divided by the dashed lines in FIGS.3A-3B. These two separate device connector modules are designated as202-1 and 202-2 in FIGS. 3A-3B. Each of the two separate deviceconnector modules 202-1 and 202-2 can include its respective set ofoptical connectors (the device connector module 202-1 includes opticalconnectors 302-1 and 304-1, while the device connector module 202-2includes optical connectors 302-2 and 304-2). A further example ofseparate device connector modules is depicted in FIG. 7, discussedfurther below. Employing two separate device connector modules insteadof an integral device connector module can allow for redundancy to beprovided, such that communication can be performed using one deviceconnector module when the other device connector module fails.

FIG. 4A illustrates another arrangement of a modular connectorinfrastructure, which includes pairs 402 of device connector modules forrespective subsets (e.g. columns) of electronic devices 104. Each pair402 includes redundant device connector modules 404 and 406 (thatprovide identical optical signal paths for the corresponding column ofelectronic devices 104). The presence of redundant device connectormodules in each pair 402 allows for flexible service or upgrade of thedevice connector modules. For example, one device connector module of apair 402 can be removed for service/upgrade, while system operation cancontinue using the other device connector module of the pair 402. Forexample, as shown in FIG. 4A, in the left-most pair 402 of deviceconnector modules, the device connector module 404 is shown as beingremoved (disengaged) from its column of electronic devices 104 toillustrate that the connector module 404 can be removed for service orupgrade, while the device connector module 406 ion the pair 402 remainsconnected to the column of electronic devices 104.

FIG. 4B illustrates a variant of the modular connector infrastructureshown in FIG. 4A. In FIG. 4B, an interconnecting connector module 410has been added that interconnects the pairs 402 of device connectormodules. As yet a further variant, instead of just one interconnectingconnector module 410, a pair of interconnecting connector modules can beused to interconnect the pairs 402 of device connector modules (similarto pair 210 shown in FIG. 2B).

FIG. 4C illustrates another example modular connector infrastructure,which includes horizontally arranged pairs of redundant device connectormodules 404 and 406, where each pair of device connector modules 404 and406 is optically connected to a respective row of electronic devices104. FIG. 4C also shows a redundant pair of interconnecting connectormodules 410 and 412. The interconnecting connector module 410 isoptically connected to the device connector modules 404, while theinterconnecting connector module 412 is optically connected to thedevice connector modules 406. The connector modules 406 and 412 providea redundant optical path in case of failure of a connector module 404 orthe interconnecting connector module 410. Similarly, the connectormodules 404 and 410 provide a redundant optical path in case of failureof a connector module 406 or the interconnecting connector module 412.

In further examples, the device connector modules 404 and 406 canelectrically connect to the electronic devices 104. In such examples,the device connector modules 404 and 406 can be electrically connectedto interconnecting connector modules 410 and 412, or alternatively, thedevice connector modules 404 and 406 can have electrical-to-opticalconversion circuitry to allow the device connector modules 404 and 406to be optically connected to interconnecting connector modules 410 and412. Note that similar electrical/optical connections can be employed inthe other arrangements discussed above.

In the ensuing discussion, although reference is made to pairs ofredundant connector modules, it is noted that in other implementations,sets of redundant connector modules can be provided, where each set caninclude two or more than two redundant connector modules (redundantdevice connector modules or redundant interconnecting connectormodules).

FIG. 5A shows an alternative example arrangement, which includesredundant electronic devices as well as redundant connector modules. Theredundant electronic devices include a first pair 502 of communicationsdevices 504 and 506, and a second pair 508 of communications devices 510and 512. Processing devices 514 are optically connected to both theredundant communications devices 504, 506 in the pair 502, whileprocessing devices 516 are optically connected to both communicationsdevices 510 and 512 in the pair 508. FIG. 5A also shows two pairs 518and 520 of device connector modules. The first pair 518 includes deviceconnector modules 522 and 524, while the second pair 520 includes deviceconnector modules 526 and 528.

The device connector module 522 connects the processing devices 516 tothe communications device 510, while the device connector module 524connects the processing devices 516 to the communications device 512.Similarly, the device connector module 526 connects the processingdevices 514 to the communications device 504, while the device connectormodule 528 connects the processing devices 514 to the communicationsdevice 506.

Since the communications devices 510 and 512 are redundant communicationdevices, even if communication between the processing devices 516 to oneof the communications devices 510 and 512 is lost (such as due toremoval of either the device connector module 522 or 524 in the pair518), system operation can continue since the processing devices 516 arestill able to connect optically communicate with the other of thecommunications devices 510 and 512. Thus, for example, if the deviceconnector module 522 were to be removed to cut off communication betweenthe processing devices 516 and the communications device 510, theprocessing devices 516 would still be able to communicate through thedevice connector module 524 with the communications device 512.

FIG. 5B shows a different example arrangement, in which the fourcommunications devices 504, 506, 510, and 512 of FIG. 5A are replacedwith communications devices 530 and 532 in FIG. 5B. Each communicationsdevice 530 or 532 is wider than each of the communications devices 504,506, 510, and 512, to allow for connection to two device connectormodules rather than just one device connector module. For example, thecommunications device 530 is connected to both device connector modules522 and 526, while the communications device 532 is connected to bothdevice connector modules 524 and 528. The communications devices 530 and532 can be redundant communications devices, where one communicationsdevice can be used when the other communications device is inaccessibleby electronic devices, such as due to removal of one of the deviceconnector modules.

Although not shown in FIG. 5A or 5B, an interconnecting connector module(or multiple interconnecting connector modules) can also be used forinterconnecting the device connector modules 522, 524, 526, and 528. Forexample, one interconnecting connector module can be used tointerconnect device connector modules 522 and 526, while anotherinterconnecting connector module can be used to interconnect connectormodules 524 and 528.

FIG. 6 is a rear view of the rack 102 with the electronic devices 104 ofFIG. 1 removed. The rear of the rack 102 includes plenums 602, whereeach plenum 602 defines an elongated groove arranged to receive one ormultiple device connector modules, such as those shown in FIG. 2A-5B.

FIG. 7 is a rear view of an alternative example arrangement of the rack102. In FIG. 7, two types of plenums are provided, including firstplenums 702 and second plenums 704. The first plenums 702 are used toreceive device connector modules that are for communicating datasignals, which can be relatively high-speed (high-frequency) signals.Data signals can refer to information that is communicated by electronicdevices during normal operation.

The second plenums 704 are used to receive device connector modules forcarrying management signals and power distribution. Management signalsare signals used for managing electronic devices. In some examples,management signals can have reduced frequencies as compared to datasignals, and there can be usually be a smaller amount of managementsignals as compared to data signals.

As shown in FIG. 7, two device connector modules 706 and 708 arereceived in the groove of each of the first plenums 702. The two deviceconnector modules in each plenum 702 include a first device connectormodule 706 having optical connectors 714 (and other optical connectorsnot visible in the view of FIG. 7), and a second device connector module708 having optical connectors 716 and 718. In examples according to FIG.7, the optical connectors 714 and 716 of the two different deviceconnector modules 706 and 708 are interleaved with respect to each otherso they can be positioned closed to a center longitudinal location ofthe plenum 702.

Each plenum 704 receives device connector modules having its respectiveset of optical or electrical connectors 720.

Fan assemblies 710 can also be mounted in the rack 102. The fanassemblies 710 can be mounted in respective fan receptacles 712—theleft-most two fan receptacles 712 are shown without their respective fanassemblies 710. The device connector modules in the plenums 704 can alsocarry power distribution and fan management signals for the fanassemblies.

FIG. 8 illustrates another example arrangement of the rack 102. The rack102 includes plenums 602 for receiving device connector modules toconnect to corresponding electronic devices mounted in the rack. Inaddition, FIG. 8 shows an interconnecting connector module 802 forinterconnecting the device connector modules in the plenums 602. Thisallows for intra-rack optical communications between the deviceconnector modules, where electronic devices connected to one deviceconnector module can communicate with electronic devices connected toanother device connector module.

Although just one interconnecting module 802 is shown in FIG. 8, adifferent arrangement can include multiple interconnecting connectormodules 802.

FIG. 9 is a flow diagram of a process of assembling a modular connectorinfrastructure, in accordance with some implementations. The process ofFIG. 9 can be performed at a manufacturing facility of a modularconnector infrastructure according to various implementations.Alternatively, the process of FIG. 9 can be performed by another entityfor assembling a modular connector infrastructure.

The process includes providing (at 902) first type connector modules(e.g. device connector modules discussed above), which can be opticallyconnected to corresponding subsets of electronic devices arranged in arack. In some examples, each subset of electronic devices can beconnected to a single first type connector module. In other examples,each subset of electronic devices is connected to a respective set ofredundant first type connector modules.

The process of FIG. 9 further optically connects (at 904) at least onesecond type connector module (e.g., interconnecting connector modulediscussed above) to optically interconnect the first type connectormodules.

With modular connector infrastructures according to variousimplementations, a flexible modular design of a backplane infrastructureis provided, that allows for the modular connector infrastructures to berelatively easily serviced, upgraded, or modified. The modular connectorinfrastructure is also scalable to support either a full arrangement ofelectronic devices in a rack or a partial arrangement of electronicdevices in a rack.

In the foregoing description, numerous details are set forth to providean understanding of the subject disclosed herein. However,implementations may be practiced without some or all of these details.Other implementations may include modifications and variations from thedetails discussed above. It is intended that the appended claims coversuch modifications and variations.

What is claimed is:
 1. A modular connector infrastructure comprising:device connector modules having optical connectors to optically connectto respective subsets of electronic devices in a system; and a firstinterconnecting connector module to optically interconnect the deviceconnector modules, the first interconnecting connector module extendingacross the device connector modules and optically connected to each ofthe device connector modules; a second interconnecting connector moduleto optically interconnect the device connector modules, the secondinterconnecting connector module extending across the device connectormodules and optically connected to each of the device connector modules,the first and second interconnecting connector modules being redundantinterconnecting connector modules, wherein continued communicationsbetween the electronic devices is allowed through one of the first andsecond interconnecting connector modules when another of the first andsecond interconnecting connector modules is removed or has failed,wherein the device connector modules are removably connected to theelectronic devices, and the first and second interconnecting connectormodules are removably connected to the device connector modules.
 2. Themodular connector infrastructure of claim 1, further comprisingadditional device connector modules having optical connectors tooptically connect to the respective subsets of electronic devices,wherein each of the subsets of electronic devices is optically connectedto a corresponding set of redundant connector modules.
 3. The modularconnector infrastructure of claim 1, wherein the removable connection ofthe device connector modules to the electronic devices allows forreplacement of at least one of the device connector modules with adifferent device connector module to perform one of servicing, upgrade,and modification of a design of the module connector infrastructure. 4.The modular connector infrastructure of claim 1, wherein each of thedevice connector modules provides one of a star topology connection andmesh topology connection for the corresponding subset of electronicdevices.
 5. A system comprising: a rack; and a modular connectorinfrastructure in the rack and comprising: first device connectormodules having optical connectors to optically connect to electronicdevices, wherein the first device connector modules are independentlyand removably connected to the electronic devices; and second deviceconnector modules having optical connectors to optically connect to theelectronic devices, wherein the second device connector modules areindependently and removably connected to the electronic devices andprovide redundancy for corresponding ones of the first device connectormodules, wherein the first device connector modules are opticallyconnected to respective subsets of the electronic devices, and whereineach of the subsets of the electronic devices is further connected to acorresponding one of the second device connector modules, wherein aparticular one of the second device connector modules provides opticalconnectivity to a particular one of the subsets of electronic deviceswhen the corresponding first device connector module is disconnectedfrom the particular subset of electronic devices.
 6. The system of claim5, wherein the rack has plenums defining grooves to receivecorresponding first and second device connector modules.
 7. The systemof claim 5, wherein the modular connector infrastructure furtherincludes an interconnecting connector module to optically interconnectat least some of the first and second device connector modules.
 8. Thesystem of claim 7, wherein the modular connector infrastructure furtherincludes another interconnecting connector module to opticallyinterconnect at least some of the first and second device connectormodules.
 9. The system of claim 8, wherein the interconnecting connectormodules and the first and second device connector modules provideredundant optical paths.
 10. The system of claim 5, further comprising:plenums defining grooves to receive respective pairs of the first andsecond device connector modules.
 11. A method of assembling a modularconnector infrastructure, comprising: providing first device connectormodules having optical connectors for optical connection to electronicdevices in a rack, wherein the first device connector modules areindependently and removably connected to the electronic devices; andproviding second device connector modules having optical connectors foroptical connection to the electronic devices, wherein the second deviceconnector modules are independently and removably connected to theelectronic devices, wherein the first device connector modules areoptically connected to respective subsets of the electronic devices,wherein each of the subsets of the electronic devices is furtherconnected to a corresponding one of the second device connector modules,and wherein a particular one of the second device connector modulesprovides optical connectivity to a particular one of the subsets ofelectronic devices when the corresponding first device connector moduleis disconnected from the particular subset of electronic devices. 12.The method of claim 11, further comprising: optically connecting aninterconnecting connector module to the first device connector modules,wherein the interconnecting connector module is removably connected tothe first device connector modules.
 13. The method of claim 12, furthercomprising: optically connecting an interconnecting connector module tothe second device connector modules, wherein the interconnectingconnector module is removably connected to the second device connectormodules.